Essentially, then, he was a philosopher and a teacher, but he was called upon to play a part in the world of action. Following the passage already quoted, wherein Philo speaks of the blessings of the life of contemplation that he had led in the past,[70] he goes on to relate how that "envy, the most grievous of all evils, attacked me, and threw me into the vast sea of public affairs, in which I am still tossed about without being able to make my way out." A French scholar[71] conjectures that this is only a metaphorical way of saying that he was forced into some public office, probably, a seat in the Alexandrian Sanhedrin; and he ascribes the language to the bitter disappointment of one who was devoted to philosophical pursuits and found himself diverted from them. Philo's language points rather to duties which he was compelled to undertake less congenial than those of a member of the Sanhedrin would have been; and probably must refer to the polemical activity which he was called upon to exert in defending his people against misrepresentation and persecution. During the reign of Augustus and the early years of Tiberius (30 B.C.E.-20 C.E.) the Roman provinces were firmly ruled, and the governors were as firmly controlled by the emperor. To Rectus, who was the prefect of Egypt till 14 C.E., and who was removed for attempted extortion, Tiberius addressed the rebuke, "I want my sheep to be shorn, not strangled." But when Tiberius fell under the influence of Sejanus, and left to his hated minister the active control of the empire, harder times began for the provincials, and especially for the Jews. Sejanus was an upstart, and like most upstarts a tyrant; and for some reason--it may be jealousy of the power of the Jews at Rome--he hated the Jewish race and persecuted it. The great opponent of Sejanus was Antonia, the ward of Philo's brother, and a loyal friend to his people; and this, too, may have incited Sejanus' ill-feeling. Whatever the reason, the Alexandrian Jews felt the heavy hand, and when Philo came to write the story of his people in his own times, he devoted one book to the persecution by Sejanus. Unfortunately it has not survived, but veiled hints of the period of stress through which the people passed are not wanting in the commentary on the law.